Abstract: During the whole life cycle, in-service platforms are subjected to severe sea conditions for a long time, making it difficult for sacrificial anode protection systems to maintain the expected protection effect. A 1/8 scale model was established for a test platform in the South China Sea. The coating breakage was simulated by controlling the electrical connection between the scale model and the bare steel plate. A rapid repair device was designed based on the applied current cathodic protection method. Numerical simulations were used to establish the optimum deployment plan for the device. Real sea tests were carried out in the waters of Xiaoping Island. The results show that the rapid repair device could effectively repair the coating damage of in-service platforms. The numerical simulation method was found to be reliable and accurate in the design of the rapid repair scheme.